共查询到20条相似文献,搜索用时 8 毫秒
1.
Y. A. Hekster A. M. Baars T. B. Vree B. Van Klingeren A. Rutgers 《International journal of clinical pharmacy》1979,1(1):695-700
The present study compares the determination of the plasma concentrations of ampicillin, amoxycillin and cefuroxime in rabbits, by means of high performance liquid chromatography and the microbiological assay. The correlation coefficient between the data obtained by these methods are for ampicillin 0.991, amoxycillin 0.994 and cefuroxime 0.991. Plasma constituents interfering with amoxycillin in theHplc determinations, were not encountered in the plasma of man. 相似文献
2.
梁尚栋 《中国药理学与毒理学杂志》1998,(2)
用荧光素-荧光素酶方法测定大鼠盆总神经节腺苷三磷酸(ATP)释放.钠通道阻断剂河豚毒素(1μmol·L-1)抑制电刺激诱发的盆总神经节ATP的释放.灌流液中去除Ca2+并加入EGTA(1mmol·L-1)后消除ATP的释放.腺苷(100μmol·L-1),A1腺苷受体激动剂环戊腺苷(0.1μmol·L-1),毒蕈碱性受体激动剂氧化震颤素(1μmol·L-1)和5-羟色胺(100μmol·L-1)减少ATP的释放.A1腺苷受体拮抗剂8-环戊基-1,3-二丙基黄嘌呤(10nmol·L-1),α2肾上腺素受体拮抗剂育亨宾(3μmol·L-1),D2多巴胺受体拮抗剂舒必利(20μmol·L-1)和组胺(100μmol·L-1)增加ATP的释放.结果提示,在大鼠盆总神经节存在着作为神经递质参与突触传递的ATP释放.A1腺苷受体,毒蕈碱性受体,α2肾上腺素受体,D2多巴胺受体,5-羟色胺受体及H1组胺受体激动剂或拮抗剂可以通过节前机制影响ATP的释放 相似文献
3.
4.
AnalysisofelectronicstructuresofphysostigmineanalogsHUZengJian,JIANGHuaLiang,CHENJianZhong,CHENKaiXian1,JIRuYun(Shanghai... 相似文献
5.
《中国药理学与毒理学杂志》1991,(4)
<正> It was suggested that adriamycin (ADM) may have at least two mechanisms of tissue damage. One, which involves lipid peroxidation, is blocked by the free radical scavenger, appears to play a major role in the development of cardiomyopathy. The other, which may involve binding of ADM to DNA, appears to be the major determinant of ADM toxicity for tumor cells. So the antitumor efficiency of ADM may be dissociated from its side effect of 相似文献
6.
《中国现代医药杂志》2006,(9)
转化及土壤重金属污染的治理等方面起重要作用,关于有机酸是否影响矿物风化的问题,自1826年Sprengel和Julien为土壤中的有机酸是否在矿物溶解中扮演重要角色展开争论以来,已经持续 相似文献
7.
A quantitative behavioural test system based on Herrnstein's (1970) equation was used to test a prediction derived from the anhedonia hypothesis of neuroleptic action, that pimozide should increase the value of the behavioural parameter K
H
(the reinforcement frequency needed to maintain the half-maximal response rate in variable-interval schedules). On the basis of theoretical considerations, it was shown that the equation implies that a drug which exerts such an effect on K
H
must have a more profound suppressant effect on performance maintained by low reinforcement frequencies than on performance maintained by high reinforcement frequencies. Fifteen rats were trained under variable-interval 10-s and variable-interval 100-s schedules, and the effect of pimozide (0.125, 0.25, 0.33, and 0.5 mg/kg) was tested on performance maintained under each schedule. The drug suppressed performance maintained under both schedules in a dose-dependent manner, and there was no tendency for the drug to exert a greater effect on performance maintained under the lower reinforcement frequency. These results do not provide any evidence that the effect of pimozide on variable-interval performance is due to an anti-hedonic effect; rather, they are compatible with the hypothesis that pimozide impairs the capacity to respond. 相似文献
8.
1.患者简介患者,女性,19岁,妊娠25周时,出现头痛,恶心,上腹部不适,血压162/108 mmHg,间隔6小时后再测血压,仍是162/108 mmHg。患者无高血压患病史。尿蛋白检查:+诊断:子痫前期(原名先兆子痫)2.用药 相似文献
9.
Mei - mi Zhao Zan Teng Zhi Li Hong - rui Liu Jin - sheng Zhao Xiu - hua Yu Ying Fan Yasuo Watanabe 《中国药理通讯》2005,22(4):43-44
Aim Bronchial asthma is a chronic inflammatory disease of the airways, is characterized by massive infiltration of eosinophils and airway hyperreactivity ( AHR), which are caused by overproduction of inflammatory factors. It was reported that Scoparone possessed anti-inflammation and calcium antagonistic effects. We found that the dilatory effect of scoparone on the tracheal smooth muscle of guinea-pig, hence we presumed that scoporone might cure bronchial asthma. There has not been any report about anti-inflammation activity of scoparone on asthma, so we investigated the anti -inflammation activity of scoparone via using asthmatic models of guinea pig. 相似文献
10.
Molinate is a preemergent herbicide that has been demonstrated to affect reproduction in the rat via alterations in sperm production. A wealth of standard toxicological studies and targeted research efforts relating to this adverse effect is available, and these were used to evaluate the utility of the Human Relevance Framework (HRF) for noncancer health effects. The hypothesized mode of action involved inhibition of the hydrolysis of cholesterol from high-density lipoprotein in the rat testes, followed by an androgen withdrawal syndrome on spermatogenesis. Some evidence is available that a similar mode of action would not be operable in humans. Despite the wealth of studies conducted in the rat, the weight of evidence is insufficient to define the mode of action for reproductive toxicity in the male rat. A principal deficiency in the database was discordance between the exposure levels observed to cause biochemical disturbances in the testes related to the hypothesized mode of action and the dose levels observed to induce the adverse outcome on spermatogenesis. For this reason, a complete MOA/human relevance analysis is not possible and, based on traditional risk assessment principles, any toxic effects are assumed to be relevant for human risk assessment. 相似文献
11.
K. L. Woods S. P. Linton M. J. Kendall E. B. Faragher R. J. Grieve 《European journal of clinical pharmacology》1979,15(4):229-233
Summary The effects of intravenous propranolol, metoprolol, acebutolol and placebo on exercise-induced changes in heart rate and peak flow rate (PFR) have been studied in a group of healthy subjects. The three -blockers produced significant and comparable reductions in exercise-induced tachycardia and the magnitude of the reduction was related to the log plasma concentration of each drug. Significant cardiac -blockade was detectable for three hours after giving propranolol and for four hours after metoprolol and acebutolol. The exercise-induced changes in PFR were small and variable and were not significantly affected by any of the drugs. We conclude that, contrary to published reports, exercise-induced changes in heart rate and PFR in healthy subjects do not provide a satisfactory test system for assessing the selectivity of -blockers. 相似文献
12.
Peng Zhang Erli Zhang Min Xiao Chang Chen Weijian Xu 《Archives of pharmacal research》2013,36(1):109-115
Inflammation is an immune response against a variety of noxious stimuli, such as infection, chemicals, and physical injury. Eugenol, a natural phenolic extract, has drawn much attention for its various desirable pharmacological functions and is, therefore, broadly used in our daily life and medical practice. However, further usage of eugenol is greatly limited due to its unwanted properties, such as physicochemical instability, poor solubility, and high-dose cytotoxicity. In hopes of extending its applicability through glycosylation, we previously reported a novel, efficient, and high throughput way to biosynthesize α-d-glucosylated eugenol (α-EG). In this study, we further explored the potential superior properties of α-EG to its parent eugenol in terms of anti-inflammatory activities. We demonstrated that α-EG was an effective anti-inflammatory mediator in both non-cellular and cellular environments. In addition, the non-cellular inhibitory effect of α-EG could be amplified by α-glucosidase, which ubiquitously exists in cytoplasm. Furthermore, α-EG exhibited a superior anti-inflammatory effect to its parent eugenol in a cellular environment. In words, our findings collectively suggest that α-EG is a stronger anti-inflammatory mediator and may thereby serve as a desirable substitute for eugenol and a potential therapeutic prodrug in treating inflammatory diseases in the future. 相似文献
13.
《International journal of pharmaceutics》1988,46(3):217-222
Hydroxyalkylated β-cyclodextrins (HA-β-CyDs), 2-hydroxypropyl-β-cyclodextrin (HP-β-CyD), and hydroxyethyl-β-cyclodextrin (HE-β-CyD), were prepared and their physicochemical and biological properties and solubilizing abilities were studied and compared with those of parent β-cyclodextrin (β-CyD). HA-β-CyDs had much higher aqueous solubility ( > 50 w/v%) and were less hygroscopic than the parent β-CyD. Their surface activities were between those of β CyD and alkylated-β-cyclodextrins and were increased proportionately to their average degrees of substitution. The hemolytic activity (human erythrocytes) and local irritancy (rabbit muscle) of these compounds, and particularly of HE-β-CyD, were considerably less than those of natural cyclodextrin or dimethyl-β-cyclodextrin (DM-β-CyD). In contrast to surface activity, the hemolytic activity of HA-β-CyD decreased with the degree of substitution; possibly the difference in their ability to dissolve membrane components may be the reason. HA-β-CyDs were found to be powerful solubilizers of several drugs and no crystalline complexes were precipitated at high concentrations of solubilizer, a phenomenon which is often observed when β-CyD is used. HP-β-CyDs were somewhat better solubilizers than HE-β-CyDs and the preparations with the lower degrees of substitution were again better than those with the higher ones. The above data suggest that HA-β-CyDs are safer and more effective solubilizers for poorly water-soluble drugs than the parent cyclodextrin. 相似文献
14.
Summary When slices of rat dorsal caudatoputamen (= neostriatum) are incubated in vitro, Choecystokinin-like immunoreactivity (CCK-LI) is released upon addition of veratridine (3.75 mol/l). This release is affected by dopamine and by -aminobutyric acid (GABA)-receptor agonists. Dopamine enhances the release by stimulating dopamine D2-receptors and decreases it via D1-receptors. GABAA-receptor agonists enhance the veratridine-induced release of CCK-LI, while GABAB-receptor agonists decrease it. In the present investigation, it was examined whether GABA-receptors are involved in the effect which dopamine exerts via D2-receptors. The GABAA-receptor antagonist bicuculline (10 mol/l)and the blocker of the GABAA-receptor ionophore picrotoxin (1 mol/l) did not affect the dopamine (0.1 mol/1)-induced increase in the release of CCK-LI. However, the GABAA-receptor agonist muscimol (1 mol/l) not only enhanced the release of CCK-LI, but also prevented a further enhancement by dopamine (0.1 mol/l). This effect of muscimol was blocked by bicuculline (10 mol/l). In the presence of -amino-n-valeric acid (0.1 mmol/l), which has been described to block GABAB-receptors, dopamine no longer enhanced the veratridine-induced release of CCK-LI. -Amino-n-valeric acid also inhibited the pronounced enhancement of the release of CCK-LI caused by dopamine (0.1 mol/l) and 1 mol/l in the presence of the preferential D1-receptor antagonist SCH 23390. The effect of -amino-n-valeric acid persisted in the presence of bicuculline (10 mol/l and 100 mol/l). (+)-Baclofen, a partial agonist at GABAB-receptors, and the stereoisomer (–)-baclofen, a full agonist, also prevented the effect of dopamine on the veratridine-induced release of CCK-LI. The effects of both drugs may be due to desensitization of GABAB-receptors, which has been described to develop quite rapidly. It is concluded that -amino-n-valeric acid blocks GABAB-receptors and in this way prevents the enhancement of the veratridine-induced release of CCK-LI caused by dopamine via D2-receptors. These data are interpreted as evidence that dopamine and GABA-neurons can directly or indirectly interact in the rat neostriatum.
Send offprint requests to D. K. Meyer at the above address 相似文献
15.
The biopharmaceutical assessment of new drug candidates based on their chemical structure is important in drug discovery and development. The scope of this study is to focus on lipophilic drugs and to clarify the role of their chemical predictors on oral bioavailability in humans. First their chemical properties were calculated from molecular modeling and the bioavailability data was obtained from the literature. The data was then analyzed by a partial least square method including non-linear terms. Significant coefficients were identified from a group of polarity- and solubility-related properties. Contour plots were constructed mapping molecular weight together with different polarity factors. Depending on the molecular weight a maximal bioavailability was found at solubility parameters of about 31–35 (J/cm3)1/2 and HLB values of roughly 4–12. The mapping of lipophilic drugs also revealed that a solubility parameter of less than 20 (J/cm3)1/2 or a HLB of smaller than unity is critical for the drug-likeness of new compounds. 相似文献
16.
Li zhenguo 《中国药理通讯》2007,24(2):37-37
Object: To approach the biological basis of AD in eld. Methods: 15 young and 15 old healthy female rats supplied by experimental animal centre of Central South University were decapitated and the hippocampus tissues were extracted for the test of expressions of mRNA of APP cleaveing enzyme and test of protein of BACE1 and ADAM10 through RT-PCR and western blotting. Results: (1) Compaied with young rats, 相似文献
17.
A series of independently occurring episodes which were notified individually as 'food poisoning' were, after investigation, linked to a common source water supply. 相似文献
18.
Vimala H. Sethy Robert H. Roth Judith R. Walters James Marini Melvin H. Van Woert 《Naunyn-Schmiedeberg's archives of pharmacology》1976,295(1):9-14
Summary Gamma-hydroxybutyrate administered in anesthetic doses produces a time dependent increase in the levels of rat brain acetylcholine. A maximal increase in whole brain and subcortical levels of acetylcholine is observed about 15 min after administration of the lactone form of the drug. A similar GHB-induced increase in acetylcholine is observed in the striatum and a 75% increase in the hippocampus 15 min after administration of the drug. A good temporal correlation was not obtained between the increase in acetylcholine and the depth of anesthesia produced by the drug. Gamma-hydroxybutyrate did not cause a significant change in the striatal or hippocampal levels of choline. Possible mechanisms involved in the production of this increase in acetylcholine are discussed.A partial account of this paper was presented at the fall meeting of the American Society for Pharmacology and Experimental Therapeutics held at Montreal, Quebec on August 18–22, 1974 [Pharmacologist, 16, 463 (1974)] 相似文献
19.
20.
Borgert CJ 《Regulatory toxicology and pharmacology : RTP》2007,48(1):4-5
Invasive conflict of interest disclosures are now normative requirements for participation in the operations of science, pursuant to a sea of ink intended ostensibly to advocate for objectivity. Far too little ink has been devoted to a serious discussion of how well such disclosures comport with the fundamental precepts of science, whether personal disclosures are the best method to accomplish the alleged intent, how objectively decisions can be made on the basis of information about experimenters rather than on information about experiments, and whether the practice of science might actually have been subverted, rather than supported, by those requirements. This short commentary is a modest payment on that ink deficit. 相似文献